JPH11228845A - Resin composition generating heat with high-frequency - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of generating heat by the irradiation of high-frequency by compounding an ion-conductive polymer or a polymer composition having a specific surface resistivity as an essential component. SOLUTION: This resin composition contains (A) >=2 wt.% of an ion- conductive polymer having a surface resistivity of <=10<11> (Ω/(square)) or an ion-conductive polymer composition having a surface resistivity of <=1×10<11> (Ω/(square)) and (B) <=98 wt.% of a synthetic resin or a synthetic resin composition except the component A as essential components. The component A includes a polymer having ionic groups, such as quaternary ammonium salt groups or sulfonate salt groups, in the molecule, so-called an ionomer. The addition of a polyhydric alcohol such as glycerol to the component A can furthermore lower the surface resistivity of the composition. The component B preferably has a dielectric loss tangent (tan δ) of <=1.0×10<-2> measured at 1 MHz.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a high-frequency exothermic resin composition. More specifically, an ion conductive polymer having a surface resistivity of a specific value or less, or
The present invention relates to a high-frequency heat-generating resin composition using an ionic conductive polymer composition having a surface resistivity of a specific value or less.

[0002]

2. Description of the Related Art Polar resins such as polyvinyl chloride, polyvinylidene chloride, polyurethane, nylon, nitrile rubber, and phenol resin are examples of synthetic resins that generate heat in a high-frequency electric field. There is almost no fever inside. As a measure of whether or not a polymer generates heat in a high-frequency electric field, a dielectric loss tangent (hereinafter tanδ)
). A polymer having a large value tends to generate heat in a high-frequency electric field, and a polymer having a small value does not easily generate heat in a high-frequency electric field. For example, when measured at 1 MHz, the tan δ value of soft polyvinyl chloride is 4 ×
10 ^{−2 to} 1.4 × 10 ⁻¹ . On the other hand, the tan δ value of polyethylene is 5 × 10 ⁻⁴ or less. Such a t
As a method for imparting heat generation in a high-frequency electric field to a synthetic resin having a low an δ value, a quaternary ammonium salt, a 2-oxazolidinone compound, diethylene glycol, ethanolamine, barium titanate, zinc oxide, bentonite clay, carbon black, etc. A method of compounding is being studied (Ninomiya Yamato, Polymer Processing, vol. 38, No.
7). However, the compositions obtained by these methods have problems in that it is difficult to control the conditions of high-frequency irradiation, and that the synthetic resin is deteriorated due to excessive heat generation and sparks are generated. In addition, when low molecular weight materials such as diethylene glycol are used, bleed out is not effective, and when inorganic or carbon black is used, transparency is lost or coloring is difficult. There was a point.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to provide a resin composition having good high-frequency heat generation.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies on synthetic resins that generate heat when irradiated with high frequency waves. As a result, there is a close relationship between the surface resistivity of the synthetic resins and high-frequency heat generation. It has been found that a synthetic resin having a surface resistivity equal to or less than a certain value exhibits good high-frequency heat generation. The present inventors have further studied and found that an ionic conductive polymer having a specific surface resistivity or a composition containing an ionic conductive polymer composition as an essential component shows high-frequency heat generation. Reached. That is, according to the present invention, the surface resistivity is 1 × 10 ¹¹ (Ω /
□) The following ionic conductive polymer, or 2% by weight or more of the ionic conductive polymer composition (A) having a surface resistivity of 1 × 10 ¹¹ (Ω / □) or less, and a synthetic resin other than (A), or A high-frequency heat-generating resin composition is provided, which contains 98% by weight or less of the synthetic resin composition (B). Further, the synthetic resin or the synthetic resin composition (B)
The dielectric loss tangent (tan δ) measured at 1 MHz is 1.0 ×
The high-frequency heat-generating resin composition described above, which is 10 ⁻² or less, is provided. More preferably, there is provided any one of the above high-frequency heat-generating resin compositions, wherein (A) contains a polyhydric alcohol.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail. In the present invention, the surface resistivity is 1 × 10 ¹¹ (Ω /
□) The following ionic conductive polymer or the ionic conductive polymer composition (A) whose surface resistivity is adjusted to 1 × 10 ¹¹ (Ω / □) or less is used. In the following, for simplicity, the ionic conductive polymer and the ionic conductive polymer composition are collectively referred to as an ionic conductive material.
Further, the surface resistivity referred to in the present invention means that after forming the ionic conductive material, it is kept at 23 ° C. and 50% RH for 24 hours, a voltage of 10 V is applied, and the resistance value after 10 seconds is measured. A thing. When an ionic conductive material having a surface resistivity exceeding 1 × 10 ¹¹ (Ω / □) is used, good high-frequency heat generation cannot be imparted to the obtained composition, which is not preferable.

The ionic conductive material used in the present invention will be described below. Ionic conductive material used in the present invention, the surface resistivity of ^{1 × 10 11 (Ω / □} ) or less of the ionic conductive polymer or various additives are blended, the surface resistivity of 1 × 10 ¹¹ (Ω / □) selected from the ionic conductive polymer compositions prepared below. That is, only the ion conductive polymer has a surface resistivity of 1 × 1
In the case of 0 ¹¹ (Ω / □) or less, it is not always necessary to take the form of the composition. If these ionic conductive polymers have different molecular structures, the high-frequency heat-generating resin composition finally obtained will have a different high-frequency heat-generating property. It is preferable to use a resin composition having a lower value because the resin composition can provide good high-frequency heat generation to the high-frequency heat generation resin composition.

The polymer used for the ionic conductive material having a surface resistivity of 1 × 10 ¹¹ (Ω / □) or less contains an ionic group such as a quaternary ammonium salt, a sulfonate or a carboxylate in the molecule. Polymers, so-called ionomers, are mentioned. Further, polyethylene oxide, a copolymer of ethylene oxide and propylene oxide, a copolymer of ethylene oxide and epichlorohydrin, a polymer having a polyalkylene oxide chain in the molecule such as polyetherester, polyetheresteramide and the like. No. It is desirable that all of these polymers have a molecular weight of 3000 or more. When the surface resistivity of the polymer itself is 1 × 10 ¹¹ (Ω / □) or less, it can be used alone as the ionic conductive material of the present invention. In addition, the above-mentioned polymer is an illustration to the last, and is not limited to these.

Next, the surface resistivity is 1 × 10 ¹¹ (Ω / □).
Various additives to be added to the polymer as necessary to obtain the following ionic conductive material will be described. Among the above-mentioned polymers, examples of additives which are blended with a polymer having an ionic group in a molecule, that is, an ionomer, include polyhydric alcohols such as glycerol, diglycerol, and trimethylolpropane. These polyhydric alcohols have the effect of further reducing the surface resistivity of the ionomer. For example, a polyhydric alcohol is added to a polymer having a surface resistivity of 1 × 10 ¹¹ , such as an ionomer having a sodium salt of a carboxylic acid in a molecule, such as an ionomer having a surface resistivity itself higher than 1 × 10 ¹¹ (Ω / □). (Ω / □) When it is blended so as to be less than or equal to, the ionic conductive material used in the present invention is suitable. The specific compounding amount of the polyhydric alcohol is 0.1 to 30 parts by weight, preferably 1 to 20 parts by weight based on 100 parts by weight of the ionomer.

On the other hand, the additives to be added to the polymer having a polyalkylene oxide chain in the molecule among the above-mentioned polymers include alkali metal or alkaline earth metal thiocyanates, phosphates, sulfates, and halides. ,
An ionic electrolyte such as a halogen oxyacid salt is exemplified. More specifically, potassium thiocyanate, sodium thiocyanate, lithium thiocyanate, potassium perchlorate,
Examples thereof include sodium perchlorate and lithium perchlorate. The amount of these ionic electrolytes is not particularly limited, but is 0.1 to 30 parts by weight, more preferably 0.2 to 20 parts by weight, per 100 parts by weight of the polymer having a polyalkylene oxide chain. Even when the surface resistivity of the polymer having a polyalkylene oxide chain itself is 1 × 10 ¹¹ (Ω / □) or less, the surface resistivity of the polymer is further reduced by using these ionic electrolytes in combination. This makes the material more suitable as the ion conductive material used in the present invention. In addition, polyhydric alcohols such as glycerol, diglycerol, and trimethylolpropane have an action of further lowering the surface resistivity even in an ion conductive material composed of a polymer having a polyalkylene oxide chain. Therefore, it is preferable to further blend a polyhydric alcohol even with an ionic conductive material composed of a polymer having a polyalkylene oxide chain having a surface resistivity of 1 × 10 ¹¹ (Ω / □) or less. The specific compounding amount of the polyhydric alcohol is 0.1 to 30 parts by weight, preferably 1 to 20 parts by weight based on 100 parts by weight of the ionomer.

The ionic conductive material having a lower surface resistivity as described above may be used when a large amount of heat is required for the high-frequency heat-generating resin composition or when the ionic conductive material in the high-frequency heat-generating resin composition is mixed. It is particularly effective in applications where the amount needs to be reduced.

As described above, the ionic conductive material used in the high-frequency exothermic resin composition of the present invention is constituted.
The ionic conductive materials can be used alone or in combination.

On the other hand, the synthetic resin other than the ion conductive material used in the present invention or the synthetic resin composition (B) includes high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene ( L
Α-olefin homopolymers such as polyethylene, polypropylene, polybutene-1, and poly-4-methylpentene-1 such as LDPE), ethylene-ethyl acrylate copolymer (EEA), ethylene-vinyl acetate copolymer (EVA), ethylene -Acrylic acid copolymer (EA
A), polyolefin-based resins such as copolymers of ethylene and other monomers such as ethylene-propylene copolymer, ethylene-butene-1 copolymer, ethylene-propylene-diene copolymer; polystyrene-based resin; polycarbonate Resin; Polyester resin; Polyamide resin;
Polyvinyl chloride-based resin and the like can be mentioned. These can be used in the form of a composition in which a plurality of them are combined if the compatibility is good. In addition, among the resin groups described above,
Tan δ value measured at 1 MHz, such as α-olefin homopolymers such as polyethylene, polypropylene, polybutene-1, and poly-4-methylpentene-1, and polymers having a low polar monomer content even in the case of ethylene-polar monomer copolymer. When the present invention is applied to a synthetic resin having a value of 1.0 × 10 ⁻² or less and not inherently exhibiting high-frequency heat generation, the effects of the present invention can be more remarkably exhibited. Further, t measured at 1 MHz, such as a polyvinyl chloride resin and a polyamide resin.
An δ value exceeds 1.0 × 10 ^-2 , and even a synthetic resin that originally has high-frequency heat generation,
When the tan δ value is 1.0 × 10 ⁻² or less as a whole, the present invention shows a remarkable effect. In the present invention, a thermosetting synthetic resin may be used as long as it can be combined with an ion conductive material.

As described above, the high-frequency heat-generating resin composition of the present invention comprises an ionic conductive material and a synthetic resin other than the ionic conductive material used as required. In the present invention, the proportion of the ionic conductive material in the composition is set to be 2% by weight or more. If the proportion of the ionic conductive material in the composition is less than 2% by weight, the effect of imparting high-frequency heat generation to the composition is not sufficient, which is not preferable. The proportion of the ionic conductive material can be appropriately adjusted within the range of 2 to 100% by weight according to the required high-frequency heat generation. When it is desired to maintain the properties of the synthetic resin other than the ionic conductive material as the whole composition, it is preferable to adjust the blending ratio of the ionic conductive material to 2 to 40% by weight.

In the present invention, for the purpose of improving the compatibility between the ionic conductive material and a synthetic resin other than the ionic conductive material, the composition is obtained by grafting an unsaturated carboxylic acid or a derivative thereof into the composition. Such as modified polyolefins,
A compatibilizer suitable for the synthetic resin can be appropriately used. Further, if necessary, an antioxidant, a light stabilizer, an ultraviolet absorber, a flame retardant, a lubricant, an antiblocking agent, a processing aid, a pigment and the like can be added.

The above-described high-frequency exothermic resin composition of the present invention can be prepared by melt-kneading using a usual kneading roll, kneader, Banbury mixer, single screw extruder, twin screw extruder or the like. The high-frequency exothermic resin composition is used in the form of a molded product such as a film, a sheet, a tube, a pipe, or a container, depending on its use. In addition, these molded products may be a laminate including a layer made of the high-frequency heat-generating resin composition of the present invention as a constituent layer.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to embodiments. Note that these examples are illustrative and not restrictive. In the following examples, the ionic conductive materials shown in Table 1 and the synthetic resins shown below were used.・ Polypropylene: Sumitomo Chemical Co., Ltd. “Noblen WF”
905E "(density: 0.89 g / cm ³ , MI: 3 g /
10 min, melting point: 138 ° C., tan δ value (1 MH
z): 0.0005) ・ Polystyrene: “Toporex 555-57U” manufactured by Mitsui Toatsu Chemicals, Inc. (density: 1.05 g / cm ³ , M
I: 0.3 g / 10 min, Vicat softening point: 103
° C, tan δ value (1 MHz): 0.0002)

In Comparative Example 3, the materials shown in Table 2 were used as reference materials for the ion conductive material.

On the other hand, the measurement of the surface resistivity shown in Tables 1 and 2 was performed in the following procedure. After adjusting the sample to a thickness of 100 μm and keeping it at 23 ° C. and 50% RH for 24 hours,
Using “Hiresta IP” manufactured by Mitsubishi Chemical Corporation, a voltage of 10 V was applied by an HRS probe, and a value after 10 seconds was measured.

[0019]

[Table 1]

[0020]

[Table 2]

Examples 1 to 14 and Comparative Examples 1 to 4 The components shown in Table 3 were charged into a pressure type kneader and melt-kneaded. Then, press molding was performed at a hot plate temperature of 200 ° C. using a press machine to obtain a sheet having a thickness of about 1.2 mm. Next, the sheet was cut out to 100 mm × 100 mm to obtain a test sample. The test sample thus obtained was placed in a commercially available microwave oven (500 W, 1240 MHz) and irradiated with high frequency waves for 3 minutes, and immediately thereafter, the surface temperature of the test sample was measured using a surface thermometer. Table 3 shows the results.

[0022]

[Table 3]

From Table 3, it can be seen that the high-frequency heat-generating resin composition containing a predetermined amount of the ionic conductive material having a surface resistivity equal to or less than the predetermined value shown in the present invention exhibits good high-frequency heat generation. In addition, a comparison between Example 1 and Example 3 shows that the composition using an ionic conductive material whose surface resistivity is further reduced by using a polyhydric alcohol in combination further improves high-frequency heat generation. On the other hand, as shown in Comparative Example 3, it is understood that the composition in which the ionic conductive material having the surface resistivity exceeding the predetermined value is mixed has a low high-frequency heat generation property. Furthermore, as shown in Comparative Example 4, it can be seen that even if the ionic conductive material has a surface resistivity of a predetermined value or less, the high-frequency heat generation is small when the amount is less than 2% by weight.

[0024]

As described above, according to the present invention, a resin composition having good high-frequency heat generation is provided. The composition obtained by the present invention is a film, a sheet, a tube,
It is formed into a desired shape such as a pipe or a container and is suitably used in various fields as a material requiring high-frequency heat generation.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshihiro Tange 1515 Nakatsu-cho, Marugame-shi, Kagawa Prefecture Okura Industry Co., Ltd.

Claims (3)

[Claims] An ionic conductive polymer having a surface resistivity of 1 × 10 ¹¹ (Ω / □) or less, or a surface resistivity of 1 × 1
0 ¹¹ (Ω / □) or less of an ion conductive polymer composition (A) 2% by weight or more, and a synthetic resin other than (A) or a synthetic resin composition (B) 98% by weight or less. High-frequency exothermic resin composition. 2. The high-frequency wave according to claim 1, wherein the dielectric loss tangent (tan δ) of the synthetic resin or the synthetic resin composition (B) measured at 1 MHz is 1.0 × 10 ⁻² or less. Exothermic resin composition. 3. The high-frequency exothermic resin composition according to claim 1, wherein a polyhydric alcohol is contained in (A).